Development in telephone banking and online banking allows people to enjoy banking services at home. With social development and progress, banking requirements increasingly develop, such as inquiry, transfer, and payment at any time and any location. Both telephone banking and online banking cannot provide customers with desirable services at any time and any location due to some restrictions. The emergence of mobile phone banking leads to another way to provide electronic services to users. As an extension of the online banking, mobile phone banking brings great convenience to users, and therefore, mobile phone banking is expected to be popular with the wide use and technology development of mobile phones.
For the security of electronic transaction, the USB key plays a role of escort with the development of online banking. In mobile phone banking, a device supporting electronic signatures should be provided according to the electronic signature law to sign important electronic data. Traditionally, a SIM card or WAP technology functions as a USB key, or alternatively, a digital signature algorithm and a key is simply stored in a mobile phone. Compared with a USB key used on a computer, the security technologies in the prior art are weak, and therefore, a USB key is needed for mobile devices used for mobile phone banking. For example, some devices communicate data with a computer via a USB interface. Similar functionality can be applied to applications on mobile phones by practicing the solution of the present invention.